After successfully running the above command, your project should now look something like this:

Run Auto Scaffold Command in Command Prompt (Second Option)

Another way to run these commands is through the Command Prompt. To run the scaffold command, open up your command prompt and navigate to the projects root folder. Then run a command that looks like this:

Is this correct – Your trying reverse engineer a model in your project based on your ASP_Identity Database?
I have not built a model of my ASP_Identity DB so I am not sure what type of issues you are dealing with, but I have successfully connected my ASP_Identity DB to my app through a connection string in the appsettings.json file. Why do you need a code representation of the Identity DB?
To use MS Identity in your project you’re suppose to configure it in Startup.cs and then connect to the DB in appsettings.json. That appsettings.json connection string will look something like this:
“ConnectionStrings”: {
“DefaultConnection”: “Server=XXXXX;Database=ASP_Identity_DB;user id=XXXXXXX;password=XXXXXXXX;MultipleActiveResultSets=true”
}

Yeah I had a webforms .NET 4.0 project using Identity and a SQL Database. I was looking to make a new Core MVC project using EF7. When I reverse engineered the database it brought all the identity tables with it, so then I had three Database Contexts and identity stopped working.

It seems odd that it would bring in 3 databases. In the scaffold command you are specifically setting the DB name so it should only get that one DB. Your having an issue that I have not seen before.
As far as your Identity DB. I would recommend you create a new ASP.Net Core Web Application. When creating the project, select the Web App Template and set Authentication to “Individual User Accounts”. If you do this it will create an example app that is set up to authenticate for you. To connect to your Identity DB all you need to do is open up appsettings.json and paste in your connection string.
Just like that you have an app authenticating against your existing Identity DB

I ran into a gotcha involving SQL Azure. The scaffold command will look for any Sequences you have created. There are a couple of SQL Azure versions, and only the latest supports Sequences. I kept getting errors running the scaffold command until I upgraded the SQL Azure to a version that support Sequences.